Severe weather can significantly curtail outdoor activity. For example, as outdoor temperatures drop, the level of outdoor activity generally becomes limited by how much or how well a person is dressed.
One solution to support outdoor activity for a longer period is to utilize a warmer. Such warmers may operate based on a chemical reaction. However, chemical warmers can be expensive to use, or may be limited in their effective duration. Also, chemical warmers may generate more waste as their material may not be reusable or environmentally sound. Another solution is to use a battery operated warmer. However, such warmers may be too complicated to recharge via a wired connection.